<!DOCTYPE html>
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    <meta charset="UTF-8" />
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    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      var isValid = function (s) {
        let left = '([{'
        let right = ')}]'
        let stack = []
        for (let i = 0; i < s.length; i++) {
          if (left.includes(s[i])) {
            stack.push(s[i])
          } else {
            let leftChar = stack.pop()
            if (!isPali(leftChar, s[i])) {
              return false
            }
          }
        }
        if (stack.length) return false
        return true

        function isPali(leftChar, rightChar) {
          if (leftChar == '(' && rightChar == ')') return true
          if (leftChar == '{' && rightChar == '}') return true
          if (leftChar == '[' && rightChar == ']') return true
          return false
        }
      }
      console.log(isValid('()[]}'))
    </script>
  </body>
</html>
